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Transition metal sulfides (TMSs) are favorable as electrode materials for supercapacitors (SCs) because of their high theoretical capacity, low cost, fascinating redox reversibility, electronic conductivity, and reduced charge transfer resistance. However, TMS electrodes suffer from weak compatibility and combination at heterogeneous interfaces, resulting in TMS stripping and electrode capacity degradation during long-term charging/discharging processes. Herein, we used a convenient, feasible, cheap, and environmentally friendly hydrothermal method to grow S/CoS2/NiS2in situ on Pien Tze Huang-based porous carbon (PZH) to promote the poor electric conductivity and unsatisfactory cycling stability of TMSs. Furthermore, TMSs can be tightly embedded on the surface of PZH to prevent falling off or collapse during long-term processes and usage. The prepared S/CoS2/NiS2/PZH electrode possessed an excellent specific capacitance of 1159.2 F g−1 at 0.5 A g−1, and after 10 000 cycles at 5 A g−1, the capacitance retention was maintained over 84.6%. This in situ method is promising for the development of stable TMS-based electrodes for supercapacitors. [ABSTRACT FROM AUTHOR]

Radioactive iodine in nuclear waste has become an unignorable problem of environmental pollution. In this work, two covalent organic frameworks (T-COF-1 and T-COF-2) with triazine units were synthesized for exceptional iodine capture via weak molecular interactions. Besides, the iodine capture capacity can be tuned via the design of building units, where the nitrogen content can be modified at the molecular level. Interestingly, T-COF-2 with higher triazine unit content affords a higher iodine uptake value. [ABSTRACT FROM AUTHOR]

Here, a tetrakaidecahedron-shaped Cu four-core supramolecule was designed to overcome the defects of supramolecules for lithium-ion batteries. With multiple metal centers, conductive ligands and abundant hydrogen bonds, this novel electrode shows excellent rate capability (459.4 mA h g−1 at 2000 mA g−1) and cyclicality (494.5 mA h g−1 after 700 cycles). [ABSTRACT FROM AUTHOR]

Although, hydrogen is a promising green energy source, current catalysts for hydrogen production cannot use the full range of visible light. In addition, these catalysts suffer from problems such as rapid charge-carrier recombination. Therefore, a simple strategy to synthesize high-performance catalysts for visible-light-driven H2 production is required. One promising method of increasing catalyst efficiency is the use of a heterojunction structure. Therefore, in this study, Zn0.5Cd0.5S–TiO2 (ZCS–TiO2) heterojunction photocatalysts were prepared via the controlled growth of Zn0.5Cd0.5S using a facile solvothermal method. The ZCS–TiO2 heterojunction photocatalysts showed high hydrogen production performance from water upon exposure to visible light as a result of the increased separation of photogenerated charges. Based on this success, we further modified the surface of the Zn0.5Cd0.5S–TiO2 catalyst with a reduced graphene oxide (RGO) cocatalyst to produce RGO/ZCS–TiO2 composite heterojunction photocatalysts. These ternary composite heterojunction photocatalysts also showed good hydrogen production from water because of the enhanced electron transport endowed by RGO and the matching band structure between Zn0.5Cd0.5S and TiO2. Furthermore, we investigated the effects of different loadings of RGO, as well as the use of physical mixtures, on the catalytic activity; the optimized 0.5%RGO/50%ZCS–TiO2 composite exhibited distinctly greater photocatalytic activity than the 50%ZCS–TiO2 and ZCS catalysts, as well as the 0.5%Pt/50%ZCS–TiO2 catalyst. Thus, our study demonstrates a new approach for obtaining highly efficient ZCS-based photocatalysts. [ABSTRACT FROM AUTHOR]

Z/E isomerism is a very important and interesting phenomenon in the field of chemistry. In many cases, people ignore the difference between Z/E isomers, and most studies investigate this hybrid system, thereby limiting the precise and in-depth understanding of the structure–performance relationship of materials. At present, only a few Z/E isomers of TPE derivatives can be separated, and the synthesis and separation of isomers modified by carborane substituents have not been reported. In this work, two Z/E isomers, namely, Z-TPE-2Car and E-TPE-2Car , with clear configuration were synthesized using an effective route. Both compounds have strong aggregation-induced luminescence (AIE) activity. The solid-state emission peaks of Z-TPE-2Car and E-TPE-2Car are 528 and 533 nm, respectively, and the emission peaks are shifted by 5 nm. The introduction of phenyl carborane substituents makes the two isomers have high solid-state fluorescence quantum yields, reaching 99% and 90%, respectively. [ABSTRACT FROM AUTHOR]

Tuning the morphology and size of coordination polymers (CPs) is an effective strategy to enable crystalline materials for desired applications. Herein, two CPs, named [Cd2(DBTP)(H2O)2]n (1) and {[Zn2(DBTP)(H2O)]·2.5H2O}n (2), were prepared by employing a rigid V-shaped and multidentate N-heterocyclic ligand 2,6-di(1H,2′H-[3,3′-bi(1,2,4-triazol)]-5′-yl)pyridine (H4DBTP) under solvothermal conditions. Their crystal morphologies and sizes were controlled by varying the type and the amount of surfactants. The morphology can be changed from bulk blocks to microflower-like hierarchical spheres assembled by nanosheets and the mean size of the microflowers is approximately 2 μm. Nanoscale 1a and 2a were further evaluated as heterogeneous catalysts for the conversion reactions of nitromethylbenzenes into benzoic acids. The results showed that nanoscale 2a is a more efficient catalyst than nanoscale 1a and their corresponding bulk counterparts. [ABSTRACT FROM AUTHOR]

To expand coordination polymers (CPs) as solid catalysts to selectively catalyze the three-component tandem click/alkynylation reaction for their fully substituted triazole skeletons, two Cu(i)-based CPs (CuI-CPs), [CuBr(aas-TPB)]n (1) and [Cu3I3(aas-TPB)2]n (2) (TPB = N,N,N-tri(3-pyridinyl)-1,3,5-benzenetricarboxamine), have been prepared. Because of the template effect of anions (Br− and I−), the structure of compounds is regulated under solvothermal conditions. CP 1 exhibited a one-dimensional (1D) chain, while the double strand framework with the Cu3I3 cluster platform was observed in 2. Furthermore, the different product selectivities of catalyzing terminal alkynes, benzyl azide and bromoalkyne to synthesize triazole skeletons have been caused by the significantly structural diversity of 1 and 2. The distinct structural feature of 2 endows it with unique multinuclear platforms (Cu3I3) and reaction pathways to promote the three-component tandem click/alkynylation cycloaddition reaction. As a result, 2 can be an outstanding catalyst candidate for sequential click/alkynylation cycloaddition, while 1 can efficiently catalyze the generation of click products. [ABSTRACT FROM AUTHOR]

Monolayer Bi2MoO6 nanosheets have been successfully prepared for the first time via a bottom-top approach with surfactant assistance, and show 8 times higher activity than bulk Bi2MoO6 for the selective oxidation of benzyl alcohol. Ultrafast charge separation and more acid–base active sites on the monolayer nanosheets are considered to be responsible for the robust photoactivity. [ABSTRACT FROM AUTHOR]

H3PMo12O40 molecules have been successfully encapsulated in the cavities of MIL-100(Fe) via a facile hydrothermal method (denoted as HPMo@MIL-100(Fe)). A series of characterization has corroborated the insertion of H3PMo12O40 within the cavities of MIL-100(Fe). The resulting HPMo@MIL-100(Fe) nanocomposites have exhibited much higher photoactivity than the original-MIL-100(Fe) toward the photocatalytic selective oxidation of benzylic alcohols and the reduction of Cr(vi) under visible light irradiation (λ≥ 420 nm). The higher photoactivity of HPMo@MIL-100(Fe) can be attributed to the integrative effect of enhanced light absorption intensity and more efficient separation of photogenerated electron–hole pairs. The host porous structure of MIL-100(Fe) can achieve a uniform composition with H3PMo12O40, which is significantly important for producing highly reactive dispersed H3PMo12O40 molecules and enhancing the photocatalytic activity of HPMo@MIL-100(Fe) nanocomposites. And the immobilized H3PMo12O40 molecules are more convenient for recycling. Importantly, almost no Fe and Mo ions leach from the MIL-100(Fe) during the reaction, which verifies the photostability of the HPMo@MIL-100(Fe). In addition, possible photocatalytic redox reaction mechanisms have been investigated. [ABSTRACT FROM AUTHOR]

Ultrathin monolayer HNbWO6 nanosheets have been successfully prepared through a simple and ultrafast ion intercalation assisted exfoliation method. These obtained highly dispersed nanosheets present enhanced photocatalytic hydrogen evolution activity compared to the nanosheets prepared by the traditionally time-consuming process. [ABSTRACT FROM AUTHOR]

To expand coordination polymers (CPs) as solid catalysts to selectively catalyze the three-component tandem click/alkynylation reaction for their fully substituted triazole skeletons, two Cu(i)-based CPs (Cu I -CPs), [CuBr(aas-TPB)] n (1) and [Cu 3 I 3 (aas-TPB) 2 ] n (2) (TPB = N,N,N-tri(3-pyridinyl)-1,3,5-benzenetricarboxamine), have been prepared. Because of the template effect of anions (Br - and I - ), the structure of compounds is regulated under solvothermal conditions. CP 1 exhibited a one-dimensional (1D) chain, while the double strand framework with the Cu 3 I 3 cluster platform was observed in 2. Furthermore, the different product selectivities of catalyzing terminal alkynes, benzyl azide and bromoalkyne to synthesize triazole skeletons have been caused by the significantly structural diversity of 1 and 2. The distinct structural feature of 2 endows it with unique multinuclear platforms (Cu 3 I 3 ) and reaction pathways to promote the three-component tandem click/alkynylation cycloaddition reaction. As a result, 2 can be an outstanding catalyst candidate for sequential click/alkynylation cycloaddition, while 1 can efficiently catalyze the generation of click products.

Monolayer Bi 2 MoO 6 nanosheets have been successfully prepared for the first time via a bottom-top approach with surfactant assistance, and show 8 times higher activity than bulk Bi 2 MoO 6 for the selective oxidation of benzyl alcohol. Ultrafast charge separation and more acid-base active sites on the monolayer nanosheets are considered to be responsible for the robust photoactivity.

H3PMo12O40 molecules have been successfully encapsulated in the cavities of MIL-100(Fe) via a facile hydrothermal method (denoted as HPMo@MIL-100(Fe)). A series of characterization has corroborated the insertion of H3PMo12O40 within the cavities of MIL-100(Fe). The resulting HPMo@MIL-100(Fe) nanocomposites have exhibited much higher photoactivity than the original-MIL-100(Fe) toward the photocatalytic selective oxidation of benzylic alcohols and the reduction of Cr(vi) under visible light irradiation (λ≥ 420 nm). The higher photoactivity of HPMo@MIL-100(Fe) can be attributed to the integrative effect of enhanced light absorption intensity and more efficient separation of photogenerated electron-hole pairs. The host porous structure of MIL-100(Fe) can achieve a uniform composition with H3PMo12O40, which is significantly important for producing highly reactive dispersed H3PMo12O40 molecules and enhancing the photocatalytic activity of HPMo@MIL-100(Fe) nanocomposites. And the immobilized H3PMo12O40 molecules are more convenient for recycling. Importantly, almost no Fe and Mo ions leach from the MIL-100(Fe) during the reaction, which verifies the photostability of the HPMo@MIL-100(Fe). In addition, possible photocatalytic redox reaction mechanisms have been investigated.

Ultrathin monolayer HNbWO6 nanosheets have been successfully prepared through a simple and ultrafast ion intercalation assisted exfoliation method. These obtained highly dispersed nanosheets present enhanced photocatalytic hydrogen evolution activity compared to the nanosheets prepared by the traditionally time-consuming process.